Can I use an Indian flag in my car as used by the politicians?

Probably you can't.The privilege of flying the national flag on vehicles is restricted to the President, Vice-President, Prime Minister, Governors and Lieutenant Governors of states, Chief Minister, Union Ministers, members of the Parliament of India and state legislatures of the Indian states (Vidhan Sabha and Vidhan Parishad), judges of the Supreme Court of India and High Courts, and flag officers of the Army, Navy and Air Force. read more

Yes ,Indian citizen(common man) can definitely fix a national flag on the car. The rules have been changed accordingly sometimes back. But it is nessesary by rules to maintain following things about it It must be clean all the time, should not get mutiliated or torn, failure to maintain it amounts to insulting of the nation. read more